دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the principal piece of equipment in the rotary table assembly;a turning device used to impart rotational power to the drill stem while permitting vertical movement of the pipe for rotary drilling. The master bushing fits inside the opening of the rotary table;it turns the kelly bushing, which permits vertical movement of the kelly while the stem is turning. See kelly bushing, master bushing.

n: the main component of the rotating machine that turns the drill string .it has a bevelled gear meachanism to create the rotation,and an opening into which bushings are fitted.

the assembly of gears and connections that spins the kelly.